We looked into this, but it would be damned expensive compared to any other surface. I don't think it's something you can do on your own without significant experience, and it's a pretty cold surface, so you're also looking at the potential cost of a heated sublayer.
I personally think it can look nice, especially with near invisible grout line.
A great shot is when you pull it off. A smart shot is when you don't have the guts to try.